37221 ÷ 4 = 9305 R1
We're going to perform division on 37221 with 4 as the divisor.

Step 1:
4 goes into 3 0 times with a remainder of 3.
Write down 0 as next digit of of the result. 
Result so far: 0
Subtract 0 from 3 to get 3.
Bring next digit (7) of the dividend behind the 3 and repeat the process: 37 / 4

Step 2:
4 goes into 37 9 times with a remainder of 1.
Write down 9 as next digit of of the result. 
Result so far: 9
Subtract 36 from 37 to get 1.
Bring next digit (2) of the dividend behind the 1 and repeat the process: 12 / 4

Step 3:
4 goes into 12 3 times with a remainder of 0.
Write down 3 as next digit of of the result. 
Result so far: 93
Subtract 12 from 12 to get 0.
Bring next digit (2) of the dividend behind the 0 and repeat the process: 2 / 4

Step 4:
4 goes into 2 0 times with a remainder of 2.
Write down 0 as next digit of of the result. 
Result so far: 930
Subtract 0 from 2 to get 2.
Bring next digit (1) of the dividend behind the 2 and repeat the process: 21 / 4

Step 5:
4 goes into 21 5 times with a remainder of 1.
Write down 5 as next digit of of the result. 
Result so far: 9305
Subtract 20 from 21 to get 1.

The final result is 9305 with a remainder of 1.